The first supernova filled the early universe with water, research suggests

Water is the essence of life. All living things on earth contain water within them. The Earth has an abundance of water, so life is abundant. This fundamental connection between water and life is partly due to the extraordinary properties of water, but partly due to the fact that water is one of the most abundant molecules in the universe.

It is made with a ratio of 1 part oxygen to 2 parts hydrogen, and has a simple and durable structure. Hydrogen originated from the primordial fire of the Big Bang and is the most common element. Oxygen is produced along with carbon and nitrogen in the centers of large stars as part of the CNO fusion cycle.

Because of its origins, we have generally assumed that oxygen (and, accordingly, water) increases in abundance over time. From the first stars to the present day, each generation threw oxygen into space in its dying moments. So while water was rare in the early universe, it is now relatively common. But new research suggests otherwise.

Astronomers classify stars into populations according to their age and metallicity. “Metal” here refers to elements other than hydrogen and helium. Like the Sun, the youngest and most metal-rich stars are called Population I. Older metal-poor stars are called Population II. The oldest stars, or the first stars to appear in the universe, are known as Population III.

Although we have never directly observed a Pop III star, it would have been a huge star made of only hydrogen and helium. The first seeds of everything around us, from the ocean to the trees to our beloved friends, were formed in the first stars. A new study posted on the arXiv preprint server claims that the Pop III star also flooded the universe with water.

The researchers modeled the explosion of an early small star (13 solar masses) and a large star (200 solar masses). Large stars are thought to be the first stars to form from primordial clouds, while small stars are thought to be the first stars to form in early stellar nurseries. It’s not quite the star of Pop III, but it’s very less metallic. When small stars died, they exploded as typical supernovae, but when large stars died, they exploded as brilliant anti-instability supernovae.

Based on simulations, these stars would have greatly enriched their environments with water. The molecular clouds formed from the remains of these stars had 10 to 30 times more water than the diffuse molecular clouds seen in the Milky Way today. Based on this, the researchers argue that by 100 million to 200 million years after the Big Bang, there was enough water and other elements in molecular clouds for life to form. .

Whether life really appeared in the universe this early is an unanswered question. There’s also the fact that water formed early, but ionization and other astrophysical processes may have destroyed many of these molecules. Water may have been abundant in the early days, but the universe entered a dry period before Pop II and Pop I stars produced the water levels seen today. But much of the water around us may have come from the first stars.